Fuel injector wiring diagram needed

Hi Ron,

Thanks so much for bringing us up to date! I'm glad the instrument cluster seems to be behaving a little better now.

Looking over your scanner results, it seems like there's still a CAN communication error of some sort.

It looks like there are a couple of CAN connectors in the left front doorsill. I wonder if moisture has gotten in there and caused some possible corrosion? I know you've checked the grounds nearby those locations, but it might be worth it to take a quick look at these connectors as well. I've attached photos below of the connector locations.

Are there any aftermarket electrical parts installed on the vehicle? I've seen an aftermarket replacement taillight that caused drivability issues and caused the vehicle to drop into "limp mode". The aftermarket taillight was interfering with the CAN communication somehow and once we installed an OEM taillight the issues cleared up immediately.

Is the battery testing out good now that you have the charging system back up and running?

Thanks, Wendy W.

Hi Ron,

If the CAN system is experiencing communication errors, it could cause the signal to activate the injector to be blocked.

Have you tried clearing all the codes since you've installed the new alternator?

Thanks, Wendy W.

Good evening, Ron,

Thank you very much for attaching the fault codes from your earlier test. I did look through them carefully, which is what made me wonder whether there could be an issue within the CAN system since there were codes for several different components. I just wanted to verify that these were "fresh" codes since the alternator replacement. Thanks for clarifying that for me.

I've attached schematics for the CAN system wiring in the door sill area.

I'll try to find an answer for you regarding how to disengage the connectors, but at first glance, it seems like the tab I circled in red may need to be pushed either up or down with a small pick. I haven't verified this yet, so please use care if you decide to try this.

Also, it's always a good idea to make sure the battery is disconnected when working on any part of the electrical system. The CAN system is especially sensitive to electrostatic discharge.

I'll keep working on trying to get you some more information, but I wanted to share what I could for now.

Thanks, Wendy W.

Hello!

Thank you so much for sending all the photos, they were very helpful!

The plastic piece that broke appears to be a Tyco socket housing, which can be found online. If you enter the part number "0305452828" and "Mercedes" in an online search engine you should be able to find it for sale for less than $10.

Then if you search for "remove Tyco pins" on YouTube, there are a few videos that show how to lift the release tab and slide out the terminals so you can reinstall them in the new socket housing. You'll likely need a small pick or automotive terminal tool, which can be found in auto parts stores or online relatively inexpensively.

To remove the smaller socket housings from the larger cable shoe (part number 0025467940) it seems like you'll need to first release the two tabs on each end with a small flat-blade screwdriver (indicated with the red arrows in the picture below). Then carefully slide the cover off by inserting the screwdriver in the area marked with green highlighting. Once the cover is off, each socket housing should be able to come out individually.

Please let me know how it goes.

Thanks, Wendy W.

Hello!

I'm glad you were able to find a way to open the trunk and that you're having success with the CAN bus connectors as well. Please keep us posted!

Thanks, Wendy W.

Hi Ron,

It looks like the X30/6 connector (cockpit voltage distributor) is located in the right front footwell. I've attached photos to show the location.

Thanks for keeping us updated! Wendy W.

Hello again Ron,

I've attached a diagram that shows the basic bus structure for this vehicle, along with the schematics for the X30/6 circuits.

I noticed that the right voltage distributor circuit (X30/4) communicates with the instrument cluster so I've also attached that schematic, along with the location of the X30/4 connector in case you wanted to check that as well.

I wouldn't necessarily expect to see much corrosion at the X30/4 connector because it isn't in the door sill area like the other circuits where you've been noticing the corrosion. It's possible that the connector has come loose somehow. It may be worth a look.

I hope this additional information helps.

Thanks, Wendy W.